Re: st: Questions about selmlog and svyselmlog

Yu,
About the first question:
The vardep of the income equation must have non missing values ONLY
for one category.
About the second:
the svyselmlog was written to Stata 8. Then, try this:
version 8: svyset [pweight = varw], psu(varpsu) strata(varstrat)
svyselmlog vardep varindep , sel() meth() boot()....
Hope this Helps,
Joao Lima
2010/10/19 Yu(Sophia) Zhang <sophia.zhangyu@gmail.com>:
> Dear statisticians,
>
> I am now working on my dissertation and am stuck by a STATA command.
> Basically, I want to run Heckman correction based on the multinomial logit
> model. I am going to use the command selmlog. However, a strange error shows
> up like this:
>
> Non-missing values of dependent variable for more than one outcome
> variable _m* not found
>
> I guess it might be associated with this statement in the help file:
>
> 1) In the output, selmlog adds to varlist a series of variables labelled
> _m[depvar_m value], except for the dhl option
>
> 2) The outcome variable depvar is observed for only one value of depvar_m.
> It is important that depvar should have missing values for any other value
> of depvar_m.
>
> But still cannot figure out what's wrong.
>
> In addition, when I want to control for sampling weights by running the
> command svyselmlog, I get another error:
>
> data not set up for the old survey estimation commands; use svyset under
> version control or use the new svy prefix.
>
> But there is no "svy: selmlog" command in STATA 11.....
>
> I wonder if someone could kindly give me some hint for these two
> problems. I have asked several people but no one were familiar with this
> problem.
>
> I appreciate your help very much.
>
> Sincerely,
>
> Yu
>
> *
> * For searches and help try:
> * http://www.stata.com/help.cgi?search
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
--
---------------------------------------------------------
João Ricardo F. de Lima
Pesquisador A - Economia Aplicada
Embrapa Semiárido
e-mail: joao.ricardo@cpatsa.embrapa.br
fone: +55 (87) 3862-1711 Ramal: 167
home-page: www.cpatsa.embrapa.br
----------------------------------------------------------
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/